The point-to-point quickest path problem is a classical network optimization problem with numerous applications, including that of computing driving directions. In this paper, we define a lower bound on the time-to-target which is both accurate and fast to compute. We show the potential of this bound by embedding it into an A* algorithm. Computational results on three large European metropolitan road networks, taken from the OpenStreetMap database, show that the new lower bound allows us to achieve an average reduction of 14.36%. This speed-up is valuable for a typical web application setting, where a server needs to answer a multitude of quickest path queries at the same time. Even greater computing time reductions (up to 28.06%) are obtained when computing paths in areas with moderate speeds, e.g. historical city centers. © 2014 Elsevier Ltd.
https://doi.org/10.1016/j.cor.2014.04.015Cite as:
@article{Ghiani_2014, doi = {10.1016/j.cor.2014.04.015}, url = {https://doi.org/10.1016%2Fj.cor.2014.04.015}, year = 2014, month = {oct}, publisher = {Elsevier {BV}}, volume = {50}, pages = {154--160}, author = {Gianpaolo Ghiani and Emanuela Guerriero}, title = {A lower bound for the quickest path problem}, journal = {Computers {&}amp$mathsemicolon$ Operations Research} }